The Salt of Southeast Asia

You've probably heard the story of how Worcestershire Sauce was invented — the one about the vat of salted fish that was forgotten and left to rot in a basement until the errant saucier discovered it, braved one last, desperate taste and . . . A new sauce was born. Sorry, Lea & Perrins. Southeast Asian cooks were using fermented fish sauce long before the auspicious Worcestershire beginnings. In Thailand, they call it nam pla; in Vietnam, nuoc mam; in both of those countries, as well as Burma, Cambodia, Laos and the Philippines, it is used with abandon as both a substitute for table salt and a flavoring.

As stinky and satisfying as a great gorgonzola, this staple is made by soaking small fish in brine and leaving the concoction to ferment in vats for up to two years. Used in everything from phad thai to pho, it's the slightly funky background scent at your favorite Thai or Vietnamese restaurant. Now it's starting to appear at "New American" restaurants as well. Once you've acquired the taste, it's hard to imagine going without it for very long.

My wife and I took a trip to Thailand last summer, and the first question many people asked us on our return was, "How is Thai food in Thailand different from Thai food in Seattle?" Our first answer: more fish sauce. In the tropics, people sweat. They have to replace that salt, which fish sauce does in abundance — making it, I suppose, not just the salt of Thailand but the Gatorade of Thailand. To balance out the extra fish sauce, more chilies, sugar and lime or tamarind are needed, which is why Jeffrey Steingarten of Vogue magazine came back from a recent trip to Thailand raving that Thai cuisine is "some of the most intensely flavorful I know, even without the chilies."

Another difference: In Thailand you'll never have a meal without a dish of nam pla prik on the table. This dipping sauce, which Thais use the way my grandfather uses ketchup (i.e., on everything), has only two ingredients: minced Thai chilies and fish sauce. You can make it at home in minutes, and it's great on a burger or pasta.

Fish sauce is readily available at Asian markets, and it's rarely more than $3 a bottle. My house fish sauce is Squid brand from Thailand, which is cheap, pungent and contains no squid. It's available at Uwajimaya and Central Market. At Siam on Broadway, cooks have been using Ruang Tong, one of the more heady brands of fish sauce, for 15 years. Siam's Surachai "Tom" Asavadejkajorn is quick to leap to the defense of his national sauce: "It's like in Chinese food they use soy sauce," he said, "but fish sauce has more flavor."

Bo Kline, chef-owner of the Typhoon! restaurants, prefers Baby (known for the plump, shirtless baby on the label), a Thai premium brand that's hard to find but worth the search. "It's more expensive, but it doesn't have the strong, pungent smell, and it's not too salty," said Kline. "If people can smell it all the way from the back of the kitchen, if it hits the wok and everybody knows what you're doing, it's too strong." She also likes another premium brand, Tra Chang, and advises you to buy fish sauce based on two criteria: clarity (look for a nice translucent amber) and price (you get what you pay for).

Baby and Tra Chang have been scarce in Seattle recently (I failed to find either at six different groceries in the International District last month), but Baby (23 ounces, $2.39) can be had from Temple of Thai (www.templeofthai.com) and Tra Chang (24 ounces, $2.29) from Thai Grocer (www.thaigrocer.com).

It would be a mistake to assume that Asian fish sauces should be reserved for Asian food. A few drops of fish sauce in tomato soup or pasta sauce adds a mysterious, tasty undercurrent. Western chefs are getting the idea. At Etta's Seafood, Tom Douglas regularly sauces fish with nuoc cham, a Vietnamese sauce based on nuoc mam. You could dismiss this as fusion or call it Northwest cuisine, but there's good evidence that fish sauce came to Asia centuries ago from the Roman Empire, where it was known as garum. This makes the Worcestershire yarn look even more contrived.

Cooked into a stir-fry or soup, fish sauce loses most of its fishy character and becomes a valuable supporting player. But when you're first experimenting with this versatile cooking companion at home, it pays to brave it head-on by making a Thai salad. The basic Thai dressing of lime juice, chili peppers, sugar, garlic and fish sauce is light and healthy, and you get to taste it as you go. Lucky you: Thai salad dressing is a bracing treat.

1. Unless your beans are perfectly fresh and tender, parboil for 3 to 5 minutes until firm but not tough. Rinse the beans under cold water.

2. Place the garlic, peanuts, dried shrimp, chilies and sugar in a large mortar or food processor and pound or process to a coarse paste. If using a processor, transfer the paste to a bowl.

3. Stir in lime juice and fish sauce. Taste the dressing for a balance of hot, sour, salty and sweet. If too hot or sour, add a bit more sugar. If not salty enough, add more fish sauce. Experiment a bit and see how the flavors evolve as you adjust each ingredient.

4. Add the tomatoes and half the beans. Pound gently with the mortar or a wooden spoon. The idea is not to crush the beans but to bruise them lightly so they absorb a bit of the dressing. Add the rest of the beans, stir, and pound a bit more.

5. Turn the salad out onto a serving plate or shallow bowl. Serve with sticky rice, jasmine rice or alone as an appetizer.

Matthew Amster-Burton is a Seattle-based freelance food writer. He posts recipes and a variety of food-related essays on his Web site at www.grubshack.com. His e-mail address is mamster@mamster.net.